This question may require migration to Meta.SE, as it could be a site-wide "bug", but I thought that I would test the waters here, to see if there is an obvious explanation.
I noticed that a question of mine had been modified, on April 16, by "Song Khmer" in the unanswered questions list, when sorted by votes1:
However, when checking the revision history, the April 16 edit, by Song Khmer, is not shown. The last modification was the "https everywhere" edit, three days prior:
I've not noticed the behaviour before. What is going on? Is it a bug, or something really obvious that I can't see?
Was it a rejected edit? If the latter, then should it really be shown in the Unanswered question list? Shouldn't the modifications listed in the Unanswered questions list, actually only be accepted modifications/edits?
1 The unanswered list, and the sorting, are irrelevant to the actual issue.